--KEY值
local key=KEYS[1]
--桶容量
local buketSize=tonumber(KEYS[2])
--令牌产出时间
local rate=ARGV[1]
--此次更新时间
local UpdateTime=ARGV[2]
--var为集合,剩余令牌数量【1】，更新时间【2】
local remain = tonumber(redis.call("hget",key,"remainToken"))
local lastRefreshTime=redis.call("hget",key,"lastRefreshTime")
--首次创建
if type(remain)=="nil"
then
    remain=math.ceil(buketSize/2)
    redis.call("hset",key,"lastRefreshTime",UpdateTime)
    redis.call("hset",key,"remainToken",remain)
    lastRefreshTime=UpdateTime
end
if(remain<=0)
    then
    local newTokens=math.ceil((UpdateTime-lastRefreshTime)/rate)
    local refreshToken=newTokens
    if(refreshToken<=0)
    then
        return 0
    end
    if(refreshToken>buketSize)
        then
        refreshToken=buketSize
    end
    redis.call("hset",key,"lastRefreshTime",UpdateTime)
    redis.call("hset",key,"remainToken",refreshToken)
    else
    redis.call("hset",key,"remainToken",remain-1)
end
return 1